On-axis ECCD by Strongly Focused mm Waves

强聚焦毫米波同轴 ECCD

• 批准号: 10480101
• 负责人: MAEKAWA Takashi
• 金额: $ 3.78万
• 依托单位: KYOTO UNIVERSITY
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (B)
• 财政年份: 1998
• 资助国家: 日本
• 起止时间: 1998 至 1999
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-10480101/
• 关键词: ECCD; ECH; Satooth Oscillation; mm waves; ECH; ミリ波; 楕円偏波

The experiments have been carried out by using the WT-3 tokamak and its 89GHz ECH system. During the first year, suppression experiments of sawtooth oscillations by means of on-axis electron cyclotron current drive (ECCD) were done by using linearly polarized mm waves, and also improvement of ECH injection system for elliptically polarized wave injection was carried out. This year, we have done the suppression experiments by using improved ECH injection system and compared the results with the previous results of the linearly polarized wave injection cases. The major results are following :(1) Sawtooth oscillations are suppressed by on-axis counter-ECCD, while both inversion radius and amplitude of sawtooth oscillations are increased by on-axis co-ECCD. The former result may be due to the decrease of the on-axis current density, while the latter results may be due to the increase of the on-axis current density.(2) Elliptically polarized waves in the range of β=-37° 〜+37°(β being the ellipticity) can be obtained by a couple of corrugated mirrors. These results have been confirmed by cold and hot tests. Theoretical calculation shows that this improves absorption rate of injection power by 50% for the oblique injection of X-mode compared with the previous linearly polarized case at the injection angle of 60 degree to the toroidal field.(3) Above prediction is tested experimentally. The results shows that improvement of 20〜30% is obtained by the elliptic polarization, although 50% improvement can not be obtained. This discrepancy from the theoretical prediction may be due to the fact that single pass absorption is not complete in the present case.

实验是利用WT-3托卡马克及其89GHz ECH系统进行的。第一年，利用线偏振毫米波进行了同轴电子回旋电流驱动（ECCD）锯齿振荡抑制实验。 ，并对椭圆偏振波注入的ECH注入系统进行了改进，今年我们利用改进的ECH注入系统做了抑制实验，并将结果与​​以往的结果进行了比较。线性偏振波注入情况下的主要结果如下：(1)同轴反ECCD抑制了锯齿振荡，而同轴共ECCD增加了锯齿振荡的反转半径和幅度。后者的结果可能是由于轴上电流密度的减小所致，而后者的结果可能是由于轴上电流密度的增加所致。 (2) 椭圆偏振波在通过几个波纹镜可以得到β=-37°~+37°（β为椭圆率）。理论计算表明，这可以提高50%的注入功率吸收率。对于X模式的倾斜注入，与先前的线性偏振情况相比，在与环形场的注入角为60度的情况下。(3)对上述预测进行了实验测试，结果表明： 20-30% 是通过椭圆偏振获得的，尽管无法获得 50% 的改进，这种与理论预测的差异可能是由于在当前情况下单程吸收不完全所致。

项目成果

M.Asakawa et al.: "Sawtooth control by on-axis electron cyclotrn current drive on the WT-3 tokamak"Proc. 17th IAEA Fusion Energy Conf.. 2. 643-646 (1999)

M.Asakawa 等人：“WT-3 托卡马克上的轴上电子回旋电流驱动的锯齿控制”Proc。

M.Asakawa et al.: "On-Axis Current Drive Experiment Using a Quasi-Optical Electron Cyclotron Heating/Current Drive System on the WT-3 Tokamak"Journal of Plasma and Fusion Research. Vol.75,No.6. 732-740 (1999)

M.Asakawa 等人：“在 WT-3 托卡马克上使用准光学电子回旋加速器加热/电流驱动系统进行轴上电流驱动实验”等离子体与聚变研究杂志。

M.Asakawa et al.: "On-axis current drive experiment using a quasi-optical electron cyclotron heating/current drive system on the WT-3 tokamak."Journal of Plasma and Fusion Research. 75. 732-740 (1999)

M.Asakawa 等人：“在 WT-3 托卡马克上使用准光学电子回旋加速器加热/电流驱动系统进行轴上电流驱动实验。”等离子体与聚变研究杂志。

M. Asakawa et al: "Sawtooth control by on-axis electron cyclotron current drive on the WT-3 tokamak"Proc. 17th IAEA Fusion Energy Conf. Vo1.2. 643-646 (1999)

M. Asakawa 等人：“WT-3 托卡马克上的轴上电子回旋电流驱动的锯齿控制”Proc。

M. Asakawa et al: "On-axis current drive experiment using a quasi-optical electron cyclotron heating/current drive system on the WT-3 tokamak."Journal of Plasma and Fusion Research. Vo1.75. 732-740 (1999)

M. Asakawa 等人：“在 WT-3 托卡马克上使用准光学电子回旋加速器加热/电流驱动系统进行轴上电流驱动实验。”等离子体与聚变研究杂志。